Genetic Relationships among Schizolobium parahybum (Vell.) Blake (Leguminosae) Ecotypes from Ecuador and other Countries

Abstract

Fifteen ecotypes of Schizolobium parahybum (Vell.) Blake collected in Ecuador (9), Brazil (3), Bolivia (1) Costa Rica (1), and Peru (1) were analyzed using Random Amplified Polymorphic DNA (RAPDs), Amplified Fragment Length Polymorphisms (AFLPs) and microsatellites (SSRs) in order to determine their genetic relationships and diversity patterns among ecotypes and to identify the origin of cultivated germplasm in Ecuador. Although AFLP markers were the most informative technique based on amplified products, SSRs clearly differentiated the ecotypes of Ecuador based on their geographical origin or genetic status into two groups: commercial ecotypes growing at western Ecuador very similar to the ecotype from Costa Rica, and native germplasm from eastern Ecuador and ecotypes from Brazil, Peru and Bolivia.

Radial wood allocation inSchizolobium parahyba

“…Recent nomenclature (Barneby, 1996; Lewis, 2010) considers Schizolobium parahyba to be a single species ranging from Central America through southeastern Brazil, although the species distribution is interrupted twice, first by the Andes and again by dry forest between the Amazon Basin and the Brazil's Matas Atlanticas (Barneby, 1996; Canchignia‐Martínez et al, 2007). These geographic disjunctions seem to be the basis for the two subspecies, one widespread, Schizolobium parahyba var.…”

“…Seeds and diaspores from all five sites sampled here appeared the same, consistent with the single species taxonomy. One modern genetic study supports a single species with disjunction of the subspecies across the Andes (Canchignia‐Martínez et al, 2007).…”

ANÁLISISDELADIVERSIDADGENÉTICADELGERMOPLASMA DE TECA (Tectona grandis L. f.) EN ECUADOR

“…(Luna -Rodríguez et al, 2005) y Schizolobium parahybum (Vell.) Blake (Canchignia -Martínez et al, 2007), en comparación con otras técnicas de genotipificación más complejas como los AFLP (polimorfismos en la longitud de los fragmentos amplificados) y los SSR (microsatélites). Los RAPD fueron muy eficientes para detectar la variación de las accesiones analizadas, con los que se obtuvieron valores de diversidad HT ≥ 0.70, que son mayores a los registrados en P. sylvestris L. (<0.37) (Szmidt et al, 1996) y P. oocarpa Schiede ex Schltdl.…”

“…(<0.40) (Díaz et al, 2001). En 15 poblaciones de S. parahybum, especie maderable nativa del Ecuador, se utilizaron diez oligonucleótidos RAPD de las series OPA y OPC y se obtuvieron de 12 a 16 productos amplificados por oligonucleótido, porcentajes de polimorfismo de 95 % y HT = 0.87 (Canchignia -Martínez et al, 2007). El alto valor de HT en este trabajo evidencia la constante recombinación genética natural que presenta Tectona grandis en Ecuador y que responde a factores bióticos y abióticos que inciden en la reproducción y diseminación de su semilla, incluido el hombre.…”

Botryosphaeriaceae associated with die‐back of Schizolobium parahyba trees in South Africa and Ecuador

“…In 1950, germplasm of S. parahyba var. amazonicum, originating from Costa Rica, was introduced to Ecuador by the Instituto Nacional de Investigaciones Agr ıcolas y Pecuarias (INIAP) (Canchignia-Martinez et al 2007) enabling the subsequent establishment of plantations of the species in that country in 1982.…”